Marathon des Sables – Are you there to compete or to complete?

If you’re perusing Base Camp Food and come across this article, there is every chance you already know about the Marathon des Sables (or MDS as it’s mainly known as) but if that’s not the case, let me introduce you. Founded by the French, the MDS is a multi-day self sufficient ultra race across the Sahara desert in Morocco and is now in its 37th year, making it one of the longest running races of its kind. Over 7 days, you will run, walk, hobble 250km (ish) and whilst you can stop to rest each night in your Bedouin style tent which thankfully you don’t have to carry, you do need to carry everything else to sustain you for your week in the desert. 

This self-sufficiency element is what can really make the difference regardless of whether your goal is to finish with no time pressures (other than not being overtaken by the camels) or whether you are out to race it. To give you some context, ‘completers’ at the back of the pack can be expected to take up to 70 hrs in total whereas those competing can be under 20 hrs……yes, that’s averaging 4:48 min/km or 7:42 min/mile in 50°C over sand!

Photo credit: @iamhazelrobertson @lukejgrobertson

Photograph Credit: @iamhazelrobertson @lukejgrobertson


For the racers, getting your pack weight as low as possible whilst meeting those nutritional needs to fuel that kind of performance is not only key but challenging. The completers on the other hand, whilst you don’t want to be carrying more than you need, arguably you do have a little more flex when it comes to the weight of your pack and thus the food you choose to take as this is where the bulk of your weight and space is taken up. 

Checking food labels for kcals and macros (carbs, fat, protein) per 100g of product is a helpful way to choose what has the best bang for your buck or pack weight in this case. Freeze-dried meals are an obvious choice to help keep your weight down and there is an abundance of brands available but these can vary in their nutritional makeup so you need to check what’s going to work for you. Be careful not to get lured in by the 800 kcal meal packet as this may just be a bigger portion size and so weigh more to accommodate this and may actually have the same kcals per 100g as another meal or brand. This method will not only give you more choice but if you only take large portions and find yourself struggling to eat it all (a race like this can negatively affect your appetite due to the heat and intensity), those kcals will just be wasted.  

Fuelling strategies

These can be different for the tortoise vs the hare and whilst the race stipulates you must have at least 2000 kcals/day, where these kcals come from can look quite different between runners. Nutritional needs are highly individual but as a general rule, carbohydrate is the body’s fuel of choice for a race like this and the faster you go the more you need. Fat is the other fuel source however even the leanest of runners have enough body fat to sustain their energy deficit over the week long race so this doesn’t need to be prioritised in food intake. Those of you aiming to complete the MDS with a slower pace, may be spending 6-10 hrs on your feet each day, so having enough on the go snacks will need to be factored into your fueling strategy. The racers on the other hand, who could be finishing in less than half that time, may choose to prioritise meals as they will have more down-time to prepare and eat. 

Regardless of how long you hope to spend out on the course each day, there are a few other factors to consider to help you perform the best you can.  If you are used to fueling on gels, this will need consideration as they don’t have an optimal weight to carb ratio due to the fluid content. Drinks powders containing carbs and electrolytes can be a good alternative to help fuel and hydrate you on the go. Training your gut to eat on the go with what you will be using during the race is just as important as training the heart and legs to prevent any gastro issues or the dreaded runner's trots. 

Optimising recovery shouldn’t be overlooked and using a recovery style shake powder containing carbs and protein is a great way to start the repair, refuel and rehydration process and should ideally be done within the golden hour of finishing. Lastly, make sure you think about how to boost morale when you’re out there. This will undoubtedly be one of the toughest things you do and having a motivated mindset can make a real difference. For those not sawing down their toothbrushes to save weight, this could be a packet of mini eggs or salami sticks but getting your favourite people to write messages on your food packs can equally raise the spirits. 

If all this seems too much with the relentless training regime, researching kit and juggling work, ready-made ultra packs might be the answer for you.  Please get in touch with us at Base Camp Food - email 

Bonne chance and bon appétit!

Photo credit: @iamhazelrobertson @lukejgrobertson

Photograph Credit: @iamhazelrobertson @lukejgrobertson


Rin Passmore (Sports Nutritionist MSc; PgCert) is a sports nutritionist specialising in all things endurance nutrition with a background in clinical dietetics. Rin has worked with ultra runners including numerous MDS runners, polar explorers including the Ice Maidens and Polar Preet along with ocean rowers such as Sarah Outen; helping them understand how to fuel the distance but also ensure they perform their best. Rin is a keen trail runner and having done the MDS herself and a number of far flung expeditions, she very much practises what she preaches. 


Photo credit: @paulcolledge Photograph credit: @paulcolledge

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